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ADU Contractors near Federal Way, WA
Zee Design & Build
570 Kirkland Way, Kirkland, WA 98033 26.2 milesZee Design & Build is a Kirkland, WA ADU contractor serving King, Snohomish, Skagit & Island Counties. Offering full-service ADU construction—garage conversions, basement units, backyard cottages & more—since 2012.
read moreHuskies Construction
1201 Monster Road Southwest, Renton, WA 98057 11.9 milesHuskies Construction in Renton specializes in home additions, ADUs, and DADUs. Services include garage conversions, granny flats, in-law suites, backyard cottages, and room additions, helping homeowners expand living space or generate rental incom... read more
Tacoma DADU
7809 Pacific Avenue, Tacoma, WA 98408 6.4 milesTacoma DADU Builders is a premier detached ADU builder serving Tacoma and Puget Sound. With 40+ years of experience, they offer turnkey ADU construction—design, permitting, and build—for investors, homeowners, and first-time buyers.
read moreSeattle Remodeling LLC
17202 Aurora Avenue North, Shoreline, WA 98133 30.8 milesSeattle Remodeling LLC specializes in ADU construction in Seattle, offering mother-in-law suites, backyard cottages, garage conversions, and granny flats. They help homeowners add value, rental income, and flexible living space.
read moreNorthwest ADU
1201 Pacific Avenue, Tacoma, WA 98402 6.2 milesNorthwest ADU is a full-service ADU contractor in Western Washington specializing in detached ADUs, garage conversions, and basement conversions. Serving Pierce, King, and Snohomish Counties, projects range from $180K–$350K+, taking 6–10 month... read more
North West Builders & Renovations
1135 Lake Washington Boulevard North, Renton, WA 98057 14.8 milesGordon T. Jacob - Multifamily | DADU | Remodel
6901 81st Street Court East, Puyallup, WA 98371 9.5 milesGordon T. Jacob is a family-run ADU builder and home remodeling contractor in South Puget Sound. Specializing in detached ADUs, backyard cottages, middle housing, and full home renovations in the Tacoma area.
read moreFTS Excavation
12714 151st Street East, Puyallup, WA 98374 13.6 milesFTS Excavation offers full-service ADU site development in South Puget Sound, Western Washington. Services include grading, utilities, septic systems, foundation excavation & permits. Certified, reliable ADU contractor for backyard homes &... read more
Mallard Brothers Construction
120 State Avenue Northeast, Olympia, WA 98501 32.2 milesMallard Brothers Construction builds ADUs & Tiny Homes in Olympia, WA. They offer attached, detached, garage conversions & ADA-accessible units, managing design, permits & construction for property owners seeking rental income or extra... read more
Elite Team Builders
701 5th Avenue, Seattle, WA 98104 20.4 milesElite Team Builders Inc. designs & builds ADUs—detached units, garage conversions & backyard cottages—in Seattle, Portland & Los Angeles. They offer custom design, quality materials & transparent pricing for lasting residential... read more
Love Construction
17025 33rd Avenue South, SeaTac, WA 98188 10 milesLove Construction builds ADU & DADU units in Seattle & Puget Sound to Passive House standards. Attached ADUs cost $85K–$280K; DADUs $175K–$550K. Includes permitting, energy modeling & a 5-year warranty.
read morePuget Sound ADU Builders
4712 South Morgan Street, Seattle, WA 98118 16.5 milesPuget Sound ADU Builders is a leader in ADU construction in western Washington state, excelling in design, construction, finishing, and permitting ADUs, DADUs, backyard cabins, garage conversions, duplexes, town homes, and multi-unit projects.
read moreEra Builders
911 Northeast 70th Street, Seattle, WA 98115 25.6 milesEra Builders is a Seattle-based ADU contractor offering detached ADU construction, design, permitting, remodeling, and commercial renovations. They handle full ADU projects compliant with Seattle zoning rules, using sustainable practices.
read moreTenhulzen Construction
16900 9th Avenue Southeast, Mill Creek, WA 98012 37.4 milesTenhulzen Construction offers ADU and DADU construction services in Washington State, providing pre-approved and custom plans. Options suit various budgets and timelines, with benefits including added property value and flexible living spaces.
read moreOther cities in Washington
- Bainbridge Island
- Battle Ground
- Bellevue
- Bellingham
- Black Diamond
- Bothell
- Bremerton
- Burbank
- Camas
- Edmonds
- Everett
- Fall City
- Kennewick
- Kent
- Kirkland
What you need to know
ADU Contractors in Federal Way, WA: Building in a Growing South King County City
Federal Way, Washington, is one of the fastest-growing cities in South King County, with a diverse population and a strong demand for affordable housing solutions. As the city continues to expand, Accessory Dwelling Units (ADUs) have become an increasingly popular option for homeowners looking to add rental income, house extended family members, or increase property value. Working with experienced ADU contractors in Federal Way, WA is essential to navigating the city's specific zoning codes, permitting requirements, and construction standards.
Federal Way ADU Regulations and Zoning Requirements
Federal Way operates under its own municipal code, separate from King County, which means ADU regulations are governed by the Federal Way Revised Code (FWRC). Homeowners and contractors must be familiar with these local rules before beginning any ADU project. Key regulations include:
- ADUs are permitted in single-family residential zones, including RS 5.0, RS 7.2, RS 9.6, and RS 35.0 zones.
- Both attached ADUs and detached ADUs (DADUs) are allowed, subject to lot size and setback requirements.
- The maximum size for a detached ADU is typically 1,200 square feet or 50% of the primary dwelling's square footage, whichever is less.
- Owner-occupancy requirements may apply, meaning the property owner must reside in either the primary home or the ADU.
- Setbacks, lot coverage limits, and height restrictions must all be carefully reviewed before design begins.
The Permitting Process for ADUs in Federal Way
Obtaining the proper permits is a critical step in any ADU construction project in Federal Way. The Federal Way Community Development Department oversees building permits, and all ADU projects must comply with Washington State Building Code (WSBC) as well as local amendments. A qualified ADU contractor in Federal Way will handle the full permitting process, including submitting architectural plans, site plans, and engineering documents. Permit timelines can vary, so working with a contractor experienced in Federal Way's specific review process can help avoid costly delays.
What to Look for in Federal Way ADU Contractors
Choosing the right contractor for your ADU project in Federal Way is crucial to a successful outcome. Here are some important qualities to look for:
- Local experience: Contractors familiar with Federal Way's zoning codes and permitting process will save you time and money.
- Licensing and insurance: Always verify that your contractor holds a valid Washington State contractor's license and carries liability insurance.
- Design-build capabilities: Contractors who offer both design and construction services can streamline the entire ADU process.
- Transparent pricing: Look for detailed, itemized estimates to avoid unexpected costs during construction.
Invest in an ADU in Federal Way Today
With Federal Way's growing rental market and rising property values, building an ADU is a smart long-term investment. Whether you're considering a garage conversion, basement ADU, or a brand-new detached unit, partnering with a knowledgeable ADU contractor in Federal Way, Washington ensures your project meets all local requirements and is completed to the highest standard. Start your ADU journey today and take advantage of one of South King County's most promising housing opportunities.